Straight Lines with no Face, Freestyle
I would use a curve to show the lines. Setting the bevel_depth of a line gives a simple tube like result. By default this uses only four sides but you can increase the bevel_resolution to get a rounder result.

import bpy

def createLine(lineName, pointList, thickness):
    # setup basic line data
    theLineData = bpy.data.curves.new(name=lineName,type='CURVE')
    theLineData.dimensions = '3D'
    theLineData.fill_mode = 'FULL'
    theLineData.bevel_depth = thickness
    # define points that make the line
    polyline = theLineData.splines.new('POLY')
    polyline.points.add(len(pointList)-1)
    for idx in range(len(pointList)):
        polyline.points[idx].co = (pointList[idx])+(1.0,)

    # create an object that uses the linedata
    theLine = bpy.data.objects.new('LineOne',theLineData)
    bpy.context.scene.objects.link(theLine)
    theLine.location = (0.0,0.0,0.0)

    # setup a material
    lmat = bpy.data.materials.new('Linematerial')
    lmat.diffuse_color = (0.0,0.0,1.0)
    lmat.use_shadeless = True
    theLine.data.materials.append(lmat)


inboundline = [(-0.98, 0.29, 0.44), (-0.18, 0.05, -0.20), (0.28, 0.57, -0.24)]
createLine('LineOne', inboundline, 0.05)